Ward Identities in the Derivation of Hawking Radiation from Anomalies

Understand

Robinson and Wilczek suggested a new method of deriving Hawking radiation by the consideration of anomalies.

• The basic idea of their approach is that the flux of Hawking radiation is determined by anomaly cancellation conditions in the Schwarzschild black hole (BH) background.
• Iso et al.
• extended the method to a charged Reissner-Nordstroem BH and a rotating Kerr BH, and they showed that the flux of Hawking radiation can also be determined by anomaly cancellation conditions and regularity conditions of currents at the horizon.